Quartz lamp.



F. G. KEYES.

QUARTZ LAMP.

APPLICATION FILED IBB.10,1913'.

1,113,218; Patented Oct. 13, 1914.

WITNESSES: IN VEN T 0/? ATTOR Er UNITED STATES PATENT OFFICE.

FREDERICK G. KEYES, OF BOSTON, MASSACHUSETTS, ASSIGNOB TO COOPER HEWITT ELECTRIC COMPANY, OF HOBOKEN, NEW JERSEY, A'CORPOBATION OF NEW JERSEY.

QUARTZ LAMP.

To all whom it may concern:

Be it known that I, FREDERICK G. Kmms,

a. citizen of the United States, and resident of Boston, county of Suifolk, State of Massachusetts, have invented certain new and useful Improvements in Quartz Lamps, of which the following is a specification.

My invention relates to the construction and formation of theanode portion of mercury vapor devices. These devices are well known and require no particular description. They "are characterized by hermetically sealed exhausted containers and the use of suitable electrodes therein. When in such lamps the electrode surfaces are large relative to the section of the vapor space actually carrying current, there will be a tendency for a certain wandering motion of the current at the surface of the electrode which is sometimes undesirable, as for example in a vapor electric lamp wherein flickering might be produced. This flickering is greatly re duced by my invention.

The actual principle I employ is illustrated in the accompanying drawings in which Figure 1 shows a side elevation of one form of my apparatus partly in section; Fig. 2 shows an end view also partly in section; and Fig. 3 shows a plan with a portion of the lamp removed above the section line 3, 3, in Fig. 1.

In the drawings, 1 represents the tubular portion-.of a container which would constitute a source of light in the case of the use of the device for illumination.

2 is the cathode portion, 4 the anode, 5 the anode condensing chamber and 6 the anode seal cup. As the construction at the cathode forms no part of the present invention and as it is claimed in another of my applications, Serial Number 747,315, filed February 10th, 1913, it will not be further described at this point and refe ence tothe above,application may be ina afara'furth'er'description thereof.

I form the anode here shown of mercury with an extension in the direction toward the cathode, the surface of this extension being relatively limited and prevent the tendency of the current to wander on the surface of the mercury by confining it to this relatively narrow extension. The means here utilized for this purpose is the screen or diaphragm, 7, which is supported by Specification of Letters Patent.

Application filed Tebrnary 10, 1913. Serial No. 747,316.

Patented Oct. 13, 1914.-

the wall of the container andhangs with its lower end Just below the surface of the mercury of the anode, 4. The current which must leave the anode on the. surface cannot pass back of the shield, 7, since this screen so nearly fits the tube, 1, as to block-the passing of the current around the sides of the screen from the larger portion of the anode, 4; thus by mere force of inability to do otherwise the current must remain relatively steady on the narrow extension of the anode.

To permit of the free passage of vapor to the anode condensing chamber, 5, an opening or aperture is provided in the shield, 7, as shown at-8. By reference to Fig. 1, it is' evident that mercury condensing in the chamber, 5, will accumulate in the anode 01f the left of the screen, 7, and that any excess Wlll pass under the lower edge of the screen to the right hand-side and that the electrode I surface at the latter point will be maintained in spite of the evaporation caused by the heat generated by the flow of current. The relation of the shield, 7, to the pocket containing the mercury, 4, is shown also in Fig. 2, and the separating gap, 9, between the bottom of the screen and the bottom of the mercury pocket there appears. N 0 separate description of Fig. 3 is required as the structure there shown has already been set forth in detail.

The operation is obvious. The normal flow of current is from the anode, 4, to the cathode and of the tube, 2, along the general path shown by the arrows in Fig. 1. The point of exit of the current from the anode is confined to a relatively small area, shown more clearly in Fig. 3, so that any material wandering of the current, or flickering of light, is prevented.

The lamp has been described in some detail without particular regard to the exact physical proportions or adjustments that maybe used in any particular case.

This invention is found very advantageous in connection with the high pressure operation in quartz containers, if for no other reason, because the quartz lamp lends itself readily to this type of construction. I do not wish to limit my invention to quartz containers, however, for other types of lamps may be used to advantage. I wish, further, to have it understood that in applying the invention to other materials than' quartz, certain modifications and details of the construction may be made without departing from the invention; that I desire to bring within its scope all devices which produce the same result by equivalent means. For example the shield, 7 need not be an integral part of the container and the opening, 8, may be otherwise located or the passage between the vapor path and the chamher, 5, may be otherwise supplied. Again other forms of the cathode formation may be utilized and so on, my invention being merely illustrated by the particular construction here shown. M invention might be said to include the bloc ing off of current from undesirable paths by the interposition of suitable definite. physical obstacles in the prohibited paths, the obstacles being effective against current flow, but not necessarily against the normal flow of vaporor effective against the proper distribution of mercury. I would call attention to the fact that the construction shown has other useful features more orless cognate thereto.

I claim as my invention:

1. In a mercury vapor apparatus, the combination with an exhausted container of quartz, a mercury anode therein, an anode condensing chamber, and a screen pervious to mercury vapor, interposed between the main body of said anode and the rest of the container and isolating an extension of the anode surface outside said screen.

2. A mercury vapor apparatus com rising a quartz container including a cathode portion, a vapor path portion and an anode portion, a mercury cathode in said cathode portion, a mercury anode in said anode portion and a screen interposed between said vapor path portion and said anode portion, said screen permitting the passage of liquid mercury constituting an active anode surface and pervious to the flow of mercury vapor from said vapor path portion.

3 A container for a mercury vapor apparatus comprising a tubular portion and a cathode portion and an anode portion, said anode portion embracing a suitable tubular condensing chamber and an anode pocket for mercury at the bottom thereof having an extension toward said tubular portion and a disk integral with the walls of the container of said device located between said tubular portion and said anode portion extending below the normal mercury level in said anode portion and dividing said anode extension from the main body of mercury in said anode chamber.

Signed at New York in the county of New York and State of New Yorkthis 8th day of February, A. D. 1913.

FREDERICK G. KEYES.

Witnesses:

GEORGE H. S'rocKBRrooE, THOS. H. BROWN. 

